Parametric Modeling

Parametric Modeling is the CAD capability of defining geometry through named parameters, constraints, and relationships among elements, so that a change to any driving value semi-automatically propagates through the rest of the model. CIMdata defines it as the use of mathematical and geometric functions to describe relationships among design elements, enabling automated regeneration when parameters change.

What it covers

• Dimensional and geometric constraints — distances, angles, parallelism, tangency.
• Equations and design tables that drive families of parts from a common skeleton.
• Sketch-based feature creation — extrude, revolve, sweep, loft.
• Bidirectional associativity between 3D model, 2D drawing, and downstream BOM and CAM.
• Variant generation by re-evaluating the parameter set for a new configuration.

Why it matters in PLM

Parametric models capture design intent as a first-class artifact, which is what makes engineering changes (and configuration management) practical at scale. A non-parametric (dumb-solid) edit fixes one geometry; a parametric edit propagates the intent.

Relationships (see sidebar)

• Part of CAD 3D Design alongside Feature Modeling and Direct Modeling.
• Supports Detailed Design and CAD Design.
• Implemented by mainstream MCAD systems including PTC Creo (whose Pro/ENGINEER predecessor essentially defined the discipline), Siemens NX, Dassault CATIA, and SolidWorks.